AT525419B1 - Method and device for classifying at least one temperature control branch - Google Patents

Abstract

Method for classifying at least one temperature control branch (K1-K4) of a molding tool (2) according to an influence on a heat balance of at least one section of the molding tool (2), the following method steps being carried out: - production of molded parts taking place in production cycles using the at least one section (3) of the mold (2) with the introduction of heat into the mold (2) and/or cyclical activation of a heating device with the introduction of heat into the mold (2), - conveying temperature control medium through the at least one temperature control branch (K1-K4) of the mold (2) to dissipate at least part of the heat introduced, - measuring at least one branch temperature profile over time (RLT01-RLT04) of the temperature control medium in at least one temperature control branch (K1-K4) over several production cycles, - analyzing an oscillation behavior of the at least one branch temperature profile (RLT01- RLT04) and/or a variable derived from the at least one branch temperature curve, in particular at least one branch heat flow, over several production cycles, and - classification of the at least one temperature control branch (K1-K4) into one of at least two categories according to greater and/or lesser influence the heat balance of at least one section (3) of the mold (2) based on the oscillation behavior.

Description

Description

The present invention relates to a method for classifying at least one temperature control branch of a mold according to an influence on a heat balance of at least one section of a mold, a temperature control device for temperature control of a mold having the features of the preamble of claim 15, and a computer program product for classifying at least one temperature control branch of the mold after the influence on the heat balance of at least the portion of the mold.

The prior art is briefly outlined below using injection molding machines and injection molds. Analogous statements also apply to general shaping machines and shaping tools.

Injection molds are temperature-controlled during production, since the introduction of the molding compound usually introduces large heat flows into the mold, whereby separate heating can also be provided under certain circumstances, so that the injection mold has an appropriate temperature before or during injection .

[0004] For this temperature control, temperature control branches are used, through which temperature control medium, for example water or oil, is conveyed. The heat from the injection mold is transferred to the temperature control medium and is thus dissipated (cooling). It may also be necessary to supply heat to the injection mold. The heat from the temperature control medium is transferred to the injection mold (heating).

A wide variety of methods for controlling or regulating the tempering medium flows are known in the prior art. Examples of this can be found in DE 102010042759 A1, EP 1717004 A1 or AT 513872 A2. In practice, controls based on set temperature differences (between the inlet and outlet of the respective temperature control branch) or set volume flows (e.g. in the form of flow rates, liters per minute) are used most frequently.

[0006] In practice, it is challenging to set these target values. It is true that simulations of the process - with or without modeling of the temperature control - are being carried out more and more often and it would certainly be possible to use the simulations to determine corresponding target values and then to use them at the actual start of production.

However, practice shows that little or no use is made of this possibility in reality, for which there are various reasons (e.g. lack of realism in the simulation, manufacture and operation of the injection mold in different companies, lack of information transfer, existing inventory of molds without simulation results or without a design plan, unknown course of the temperature control branches within the injection mold and the like).

Personnel who are responsible for setting the temperature (and the system as a whole) are therefore usually forced to carry out the setting on the basis of experience, certain general guidelines and tests (trial and error).

The general guidelines mentioned specify, for example, to use lower temperature differences in precision injection molded parts (to ensure a sufficiently homogeneous temperature distribution along the temperature control branch and to achieve faster heat dissipation). Lower temperature differences should also be used for temperature control branches close to the cavity, since their temperature distribution has a major influence on the mold surface temperature or mold cavity wall temperature and since higher heat dissipation is often necessary here as well.

It should be mentioned in this regard that the correct temperature control of the injection mold has a major and decisive influence on compliance with manufacturing tolerances in terms of dimensions, shrinkage and internal stresses of the injection molded parts - ultimately on the quality of the injection molded part to be produced. Excessive energy consumption due to the introduction of significantly larger volume flows at less important ones (i.e. we

(less relevant for the molded part properties or the quality of the molded part) temperature control branches than would be necessary for the quality claim should of course also be avoided. Due to a high delivery rate (volume flow or delivery pressure), this would lead to a high energy consumption for the supply pump, especially if this can be regulated. With temperature control branches connected in parallel, e.g. when using a temperature control media distributor, an unnecessarily high volume flow in less important temperature control branches would reduce the usable volume flow of the other, more important (i.e. particularly relevant for molded part properties or the quality of the molded part) temperature control branches.

The supply pump can also be present in decentralized temperature control units for a single machine or centrally for several machines or consumers. If the supply pump supplies several machines centrally, the temperature control medium is "taken away" from other machines due to excessive volume flows in less important temperature control branches.

[0012] Processes for finding target values for temperature control exist in the prior art per se, reference being made, for example, to AT 513872 A2. There is room for improvement in that additional information about the geometry of the tempering branches should be available.

The invention has therefore made it its task to provide a method, a temperature control device and a computer program product, whereby with as little information as possible - preferably no information - the influence that a temperature control branch on the heat balance of at least one section can be determined of a molding tool.

In a first variant of the invention, this object is achieved with regard to the method with the features of claim 1, namely by carrying out the following method steps:

- Production of molded parts in production cycles using at least one section of the mold with input of heat into the mold and/or cyclical activation of a heating device with input of heat into the mold,

- conveying temperature control medium through the at least one temperature control branch of the mold to dissipate at least part of the heat introduced,

- Measuring at least one branch temperature profile over time of the temperature control medium in at least one temperature control branch over several production cycles,

- Analysis of an oscillation behavior of the at least one branch temperature curve and/or a variable derived from the at least one branch temperature curve, in particular at least one branch heat flow, over a number of production cycles, and

- Classifying the at least one temperature control branch in one of at least two categories according to greater and/or lesser influence on the heat balance of the at least one section of the mold based on the oscillation behavior.

In a second variant of the invention, this object is achieved with regard to the method with the features of claim 4, namely by carrying out the following method steps:

- Supplying a molding compound at least to the section of the mold with the input of heat into the mold and/or activating a heating device with the input of heat into the mold,

- conveying temperature control medium through the at least one temperature control branch of the mold to dissipate at least part of the heat introduced,

- Measuring at least one branch temperature profile over time of the tempering medium in at least one tempering branch,

- Analysis of a rise or fall behavior of the at least one branch temperature profile and/or a variable derived from the at least one branch temperature profile, in particular at least one branch heat flow, and

- Classification of the at least one temperature control branch in at least two categories according to greater and/or lesser influence on the heat balance of the at least one section of the mold on the basis of the increase or decrease behavior.

The invention is based on the finding that, for example from the temperatures, the heat flows and/or the volume flows, which are often measured or calculated anyway at the start of production, for example, the information can be extracted as to which temperature control branches have a greater influence on the heat balance of the section of the mold and which temperature control branches have a lesser influence on the heat balance of the mold.

In the first variant, this is done by analyzing the oscillation behavior that occurs over several production cycles in a process running in production cycles. In the second alternative, this is done by analyzing the increase behavior that occurs, for example, at the start of production (or analogously: the decrease behavior). What the variants have in common is that the temperature control branches can be categorized by analyzing a curve behavior (oscillation behavior and/or rise or fall behavior) with regard to their influence on the heat balance of at least one section of the mold.

It should be mentioned that the second variant of the invention (analysis of the increase behavior) can also be carried out in the case of shaping processes running in production cycles (see the exemplary embodiment). The two variants of the invention can therefore also be combined.

With regard to the temperature control device, the object is achieved by the features of claim 15, namely in that a computing unit is set up to

- carry out an analysis of a rise or fall behavior and/or an oscillation behavior of the at least one branch temperature profile and/or a variable derived from the at least one branch temperature profile, in particular at least one branch heat flow, preferably over several production cycles, and

- Classify the at least one temperature control branch based on the rise or fall behavior and/or the oscillation behavior in one of at least two categories according to greater and/or lesser influence on the heat balance of at least one section of the mold.

With regard to the computer program product, the object is achieved by the features of claim 18, namely by instructions that cause an executing computer to

- to receive measured values in the form of at least one branch temperature profile over time of a temperature control medium conveyed through the at least one temperature control branch of the mold, the measured values preferably being available over several production cycles,

- carry out an analysis of a rise or fall behavior and/or an oscillation behavior of the at least one branch temperature profile and/or a variable derived from the at least one branch temperature profile, in particular at least one branch heat flow, preferably over several production cycles, and

- Classify the at least one temperature control branch based on the rise or fall behavior and/or the oscillation behavior in one of at least two categories according to greater and/or lesser influence on the heat balance of the at least one section of the mold.

The invention can be used in molds with a single temperature control branch. However, embodiments are particularly preferred in which several temperature control branches are categorized based on the differences in the rise or fall behavior and/or oscillation behavior.

In the following, reference is sometimes made to tempering branches in the plural. If nothing else is explicitly mentioned or something else is not implicitly stated, there are also statements

tion types with only one tempering branch. The same applies to the at least one branch temperature profile.

The analysis of the oscillation behavior and/or the rise or fall behavior can be carried out on at least one branch temperature profile itself or on a variable derived therefrom. A branch heat flow, for example, can be used as a derived variable, which can be calculated if, for example, a respective branch volume flow is known, for example through measurement. By using heat flows in the analysis of the oscillation behavior, distorting effects such as fluctuating temperatures or volume flows in the inlet can be eliminated.

Other variables derived from the at least one branch temperature profile that can be used for the analysis of the oscillation behavior and/or the rise or fall behavior would be, for example - an accumulated amount of heat - temperature differences between the inlet and outlet of the at least one temperature control branch (in particular when the temperature is constant, for example regulated volume flow) - as already mentioned, the outlet temperature if the inlet temperature is essentially kept constant, for example in a controlled manner - a branch volume flow, for example if the temperature difference between the inlet and outlet of the at least one temperature control branch is regulated (the branch volume flow is then an indirect flow from the Branch temperature profile derived variable)

[0025] Ultimately, therefore, any variables can be used as derived variables that correlate with the heat flow that the at least one temperature control branch conveys.

As already mentioned, the invention is based on the finding that the tempering branches can be categorized by analyzing the oscillation behavior or the increase behavior with regard to their influence on the heat balance of the mold.

[0027] As a special form of injection molding tools, tools with near-contour temperature control should be mentioned. The tempering branches in the mold insert are placed just a few millimeters away from the mold cavity wall in order to be able to influence the quality of the molded parts even more specifically.

As also already mentioned, the correct temperature control is essential for the quality of the molded part to be produced. The categorization according to the invention also makes it possible to find out which temperature control branches have a greater or lesser influence on the quality of the molded part to be produced. As a rule, temperature control branches with a relatively large influence on the heat balance of the mold / on the quality of the molded part are also spatially relatively close to at least one shaping cavity of the mold (and are therefore important for the heat balance of the mold, especially if they also dissipate high heat flows).

The categorization according to the invention enables, on the one hand, improved temperature control of the mold where it is important for the quality of the molded part, and, on the other hand, areas that are less important (e.g. in the area of mold mounting plates, with base or intermediate plates) or for which is only important for a temperature and heat dissipation that is as stable as possible (e.g. in the area of a hot runner system), but can be adequately tempered without excessive energy consumption. It should be mentioned here that, for example, in the area of mold clamping plates, temperature control often cannot be completely omitted, for example due to unfavorable thermal expansion that has to be avoided or due to heat losses that have to be avoided at unfavorable ambient temperatures (difference between mold temperature and ambient temperature).

In particularly preferred embodiments of the invention, the oscillation behavior and/or the increase behavior of the branch temperature curves is examined. In principle, however, the drop behavior of the branch temperature curves can also be used by ending the production of the molded parts or the feeding of the molding compound, the promotion of temperature

ration medium and measuring the branch temperature curves is continued. The branch temperature curves will then show temperatures falling at different rates, which also allow conclusions according to the invention to be drawn about the influence of the respective temperature control branch on the heat balance of the at least one section of the mold. The branch temperature of temperature control branches close to the cavity would, for example, drop more quickly than the branch temperature of temperature control branches that are arranged far from the cavity. The closer the temperature control branch is arranged to the cavity, the faster the oscillation is no longer detected, since no more molding compound is injected.

Instead of supplying molding compound, a heating device can also be used within the scope of the invention in order to introduce heat into the mold. This is preferably a heating device that is used in any case during operation of the mold, such as a heating device for temperature control of a hot runner system.

In preferred embodiments, the at least one section of the mold can be the entire mold. However, embodiments are also conceivable in which only part of the mold is made the subject matter of the invention.

For example, it would be possible to use only a hot runner system as at least a portion of the mold. The hot runner system could be filled with molding compound and the influence of the individual temperature control branches on the heat balance of this section could be determined from the increase behavior of the branch temperature curves (temporal behavior and heat flow in the temperature control branch). In many cases, the temperature control of hot runner systems depends on achieving the most stable operation possible. Here, too, information about which temperature control branches have a greater influence on the heat balance of the hot runner system is of course an advantage.

For example, individual heating zones of the hot runner system can be switched on (regardless of whether they are filled with molding compound or not; without production, then it is clear where the heat comes from) and the rise behavior of the individual temperature control branches can be observed. According to the invention, it can then be determined what influence the individual temperature control branches have on the heat balance of this section of the hot runner system. The same applies to switching off the heating zones. Temperature control branches with a high dissipated heat flow are spatially closer to the hot runner or at a point with greater heating capacity.

Another example of the at least one section would be molds that have multiple mold cavities (also referred to as mold cavities), so that multiple molded parts can be produced in one production cycle. The invention can preferably be used in such a way that molded parts are produced in all mold cavities in order to examine the influence of the temperature control branches on the overall heat balance in the mold.

Alternatively, only a single mold cavity or a group of mold cavities could be operated within the scope of the invention in order to examine the influence of the tempering branches on the heat balance of the section of the mold that contains this single cavity or group of cavities. An assignment of at least one temperature control branch to an individual cavity or group of cavities would thus be possible.

All temperature control branches of a mold can preferably be used according to the invention (delivery of temperature control medium, measurement of the branch temperature curves, analysis of the oscillation behavior and/or the rise or fall behavior, determining the differences, classification into at least two categories). However, use with a subset (with at least two temperature control branches) is also conceivable in principle if, for example, it is already known that individual temperature control branches are close to the cavity (generally: in the vicinity of at least one section of the mold) or not.

Temperature control branches can be connected in molds both in parallel and in series (in the fluidic sense), with mixed forms of course also being conceivable (for example parallel connection of temperature control branches connected in series).

The conveying of the tempering medium can preferably be started before the start of the production of the molded parts and/or before the feeding of the molding compound. In principle, however, it would also be conceivable to start with this at the same time or shortly after the start of production of the molded parts and/or the feeding of the molding composition.

The conveying of the tempering medium can preferably be started before the hot runner systems are switched on. In principle, however, it would also be conceivable to start with this at the same time or shortly after hot runner systems are switched on.

Water and/or oil can preferably be used as the temperature control medium. In practice, the temperature control medium used can be provided with various additives in order to maintain the required water quality.

In the context of the second variant of the invention, the feeding of the molding compound can be done once, continuously or cyclically.

[0043] Protection is also sought for a shaping machine with a temperature control device according to the invention.

[0044]Shaping machines are understood to be injection molding machines, transfer presses, presses and the like.

It is worth mentioning that the temperature control device can be integrated into the shaping machine or can be designed separately (the temperature control device is then often referred to as an add-on device or temperature control device). Embodiments are also quite conceivable, in which the functions of the temperature control device according to the invention are fulfilled by several separate devices, for example by:

- A temperature control unit, which provides a pump and a central inlet and/or

- a separate tempering media distributor, in which, for example, the temperature

sensors and / or volume flow sensors are provided and / or - a separate processing unit.

Irrespective of this, the computing unit can be designed integrally with a central machine control of the shaping machine or as a separate computing unit, for example as a ("cloud") server which is directly connected to the machine control or the sensors via a remote data transmission connection.

The temperature control device can particularly preferably contain a control or regulating device for controlling or regulating a temperature control medium flow conveyed through the temperature control branches using different setpoint values, in particular setpoint temperature differences and/or setpoint volume flows, for the temperature control branches.

[0048] For this purpose, the temperature control device can particularly preferably contain actuators which are connected by signaling to the control or regulating device and which are designed to influence the temperature control medium flows in the temperature control branches.

[0049] The actuators can be, for example, volume flow control valves, proportional valves and/or throttles, which can be controlled directly to set a desired degree of throttle opening. Another option for volume flow control is a speed-controlled (or flow rate-controlled) pump system (consisting of motor and pump). Such arrangements can also be regarded as actuators within the meaning of the invention.

The control or regulating device can of course also be connected to the temperature sensors in terms of signals. As a result, the measured values of the temperature sensors can be used as feedback for a regulation, in particular a temperature difference regulation. The same applies to any existing volume flow sensors and volume flow controls.

[0051] Particularly preferably, the control or regulating device can be designed in such a way that desired values can be selected individually for each temperature control branch or groups of branches.

to.

[0052] The control or regulating device can be formed integrally with the computing unit and/or with a central machine control of a shaping machine.

It should also be mentioned that the temperature sensors according to the invention do not have to be arranged inside the mold (but they can be). In many cases, outlet temperatures are simply measured where the temperature control branches open back into the temperature control device.

Inlet temperatures can be measured in each individual temperature control branch or in a distributor or in the immediate vicinity of a distributor if there are several, in particular parallel, temperature control branches.

The invention can be used both with recorded measurement data of the at least one branch temperature curve or with data in real time, or with a sampling time that is practical for thermal measurements, for example in the range of one second.

With regard to the computer program product, the executing computer can be the processing unit of the temperature control device according to the invention.

The computer program product can preferably also contain instructions that cause an executing computer to: - activate the molding machine to start and/or stop the production of molded parts in production cycles and/or - activate and /or to activate deactivation and/or - to activate the temperature control device and/or the shaping machine for conveying temperature control medium through the at least one temperature control branch and/or - to carry out a control or regulation of the temperature control medium flow conveyed through the at least one temperature control branch and the actuators according to the control or regulation to be controlled accordingly.

Finally, protection is also sought for a computer-readable storage medium on which a computer program product according to the invention is stored.

[0059] The fact that a temperature control medium flow conveyed through the at least one temperature control branch is controlled or regulated does not necessarily mean that a volume flow is used as a manipulated variable for the control or regulation. A control or regulation with a temperature difference can preferably be provided as the manipulated variable, with a subordinate control or regulation of the volume flows being able to be provided.

The at least one section of the molding tool can preferably be a section that is filled with a molding compound for the purpose of the molding process (including its surroundings). In principle, however, other sections of the mold that experience a significant heat input could also be examined with the invention.

[0061] The at least one branch temperature profile can preferably be measured during the course of the at least one branch temperature profile, ie after the flow has passed through the shaping tool.

In addition, the inlet temperature and/or the branch volume flow can also be measured in order to be able to calculate the branch heat flow, which is mediated by at least one temperature control branch.

It should be pointed out that instead of the volume flows mentioned in the present document, mass flows could in principle also be used.

Within the scope of the present invention, tempering can be understood to mean cooling and/or heating.

Measures described in connection with the prior art can also

be used within the scope of the invention.

The methods of the present invention can also be applied to a simulated mold. This enables a comparison between the temperature control circuits of the simulated molding tool and the temperature control circuits of the actual molding tool based on the determined oscillation behavior, increase behavior and/or decrease behavior. The individual temperature control circuits of the simulated mold can thus be assigned to the individual temperature control circuits of the actual mold. On the one hand, this makes it possible to determine whether the tempering branches of the actual mold were connected as planned. On the other hand, setpoint values can also be adjusted without changing the connections, for example for temperature difference control or volume flow control.

Further advantageous embodiments of the invention are defined in the dependent claims.

It has already been mentioned that several temperature control branches can be used and that the differences between the temperature control branches in the oscillation behavior and/or in the rise or fall behavior are used for the classification of the temperature control branches.

[0069] Preferably, as part of the analysis of the oscillation behavior of the at least one branch temperature curve, an amplitude, a frequency and/or a period of the at least one branch temperature curve or the derived variable, such as a heat flow, can be determined and used to determine the differences in the oscillation behavior .

In particular, a Fourier transformation can be used, for example, to examine the degree to which the cycle time (or, equivalently, the cycle frequency) of the production cycles is reflected in the branch temperature curves. In principle, of course, other (integral) transformations can also be used for this.

In principle, it would also be conceivable to carry out analyzes of the rise and/or fall behavior in each cycle as part of the analysis of the oscillation behavior.

As part of the analysis of the rise behavior, a point in time of the first rise above a threshold value in the at least one branch temperature profile can be determined and optionally used to determine the differences in the rise behavior. For example, the “point in time” may simply be the number of the production cycle if the production cycles are numbered from the start of production in an obvious way (e.g. incremented by an injection signal for screw advance or other signals describing the injection of the molding compound). Of course, the time of the first rise can also be determined with a higher time resolution.

It would also be possible, as part of the analysis of the drop behavior, to determine a time delay between a production stop (no more supply of the molding material) and the start of the drop in the at least one branch temperature profile or the variable derived therefrom.

[0074] As an alternative or in addition, a slope of the rise or fall can also be determined in the analysis of the rise or fall behavior.

According to the invention, the temperature control branches can be divided into at least two categories, i.e., for example, temperature control branches,

- whose Fourier transformations of the corresponding branch temperature curves or the corresponding derived quantities in the range of the cycle frequency have a higher maximum than other tempering branches, and/or

- whose oscillation amplitude in the corresponding branch temperature curves or the corresponding derived variables, preferably in the range of the cycle frequency, is greater

ßer than the oscillation amplitude of other tempering branches and / or

- Whose point in time of the first increase in the corresponding branch temperature curves are earlier than those of other tempering branches and/or

- Whose slope of the corresponding branch temperature curves is greater in terms of absolute value and/or

- the dissipated heat flow is greater than that of other temperature control branches and/or,

- whose accumulated amount of heat is greater than that of other tempering branches,

be classified in a category with greater influence on the heat balance of the mold (and thus greater influence on the quality of the molded part to be produced) and the remaining tempering branches in a category with lesser influence.

[0077] As part of the analysis of the rise or fall behavior, however, a key figure for the strength of the rise or fall (for example in the form of an exponential coefficient) can also be determined.

It can particularly preferably be provided that at least one setpoint value for controlling or regulating the flow of temperature control medium conveyed through the at least one temperature control branch is defined on the basis of the categories of the at least one temperature control branch.

Of course, it can preferably be provided that these target values are selected such that in the case of temperature control branches with a greater influence on the heat balance of at least one section of the mold (and thus on the quality of the molded parts produced), larger flows of temperature control media are achieved (or vice versa). : that in the case of tempering branches with less influence on the heat balance of at least one section of the mold (and thus on the quality of the molded parts produced), lower tempering medium flows are achieved).

[0080] Target values for this can be selected individually for each branch or groups of branches.

[0081] The specification of setpoint values for a control or regulation is understood to mean both the correction of setpoint values that are already present and the original specification of the same.

Preferably, at least one setpoint temperature difference between an inlet temperature and an outlet temperature of the at least one temperature control branch can be used as at least one setpoint value, with the setpoint temperature differences for temperature control branches with a greater influence on the heat balance of the at least one section of the mold preferably being lower in absolute terms be set as the setpoint temperature differences for tempering branches with less influence on the heat balance of the at least one section of the mold.

Target temperature differences have the advantage that volume flows through the individual temperature control branches do not have to be specified in detail. Rather, they arise, for example, as part of a subordinate control of the volume flows. At the same time, maintaining the temperature difference ensures that adequate heat flows are dissipated from the mold and a sufficiently homogeneous temperature distribution can be guaranteed over the length of the temperature control branch.

It should also be mentioned that the inlet temperature is measured in many cases in a central inlet (also referred to as the inlet), so that each temperature control branch does not require its own temperature sensor for the inlet temperature. In fact, especially in larger companies, one can simply assume a known constant inlet temperature, which is provided by a device for providing temperature control medium (main example: water) for a production cell or even the entire company. However, separate flow temperatures can also be specified for each temperature control branch (temperature control with individual temperature control units).

In principle, it is alternatively or additionally also conceivable that setpoint values

Volume flows are used, with the target volume flows for temperature control branches with a greater influence on the heat balance of the at least one section of the mold relative to a maximum achievable volume flow (of the respective temperature control branch) being selected to be larger than for temperature control branches with a lesser influence on the heat balance of the at least one section of the mold.

The maximum volume flow that can be achieved for each temperature control branch generally depends on the pressure available in the supply line and the geometry of the temperature control branch. This data can be taken into account when establishing and/or calculating the target volume flows.

In particularly simple embodiments of the invention, actuators, such as adjustable throttles, for temperature control branches with a greater influence on the heat balance of at least one section of the mold can be fully opened or remain (e.g. degree of throttle opening 100%) and those with less influence on the heat balance of the at least one section of the mold can be closed up to a certain percentage (e.g. degree of throttle opening 80% or 50%). If necessary, this can even be done manually at the suggestion of the at least one computing unit. However, embodiments may be preferred in which the actuators are controlled by the at least one computing unit.

[0088] Actuators for the controlled or regulated influencing of the temperature control medium flow conveyed through the at least one temperature control branch can be made equivalent at the beginning of the method, in particular can be fully opened. By equating the actuators, the branch temperature curves become particularly meaningful with regard to their influence on the heat balance of at least one section of the mold, because then no systematic deviations are introduced by differently throttled temperature control branches.

The fact that the actuators are equalized "at the beginning" of the method can be understood to mean that the equalization is carried out before the tempering medium is conveyed through the tempering branches. Of course, it is alternatively conceivable in principle for the actuators to be put on an equal footing at the same time as the start of conveyance of the tempering medium or shortly thereafter.

Several temperature control branches can be used and the actuators for the controlled or regulated influencing of the temperature control medium flows conveyed through the temperature control branches can be set at the beginning of the method in such a way that the temperature control medium flows are equalized by the temperature control branches.

This means that the volume flows of the individual temperature control branches can be regulated to the same desired value and thus, for example, kept constant. Since the heat flow in the temperature control medium is determined from the product of the volume flow and the temperature difference, along with other factors (constant), it can be sufficient to consider the behavior of the outlet temperature of a temperature control branch at a constant inlet temperature in order to carry out the analyzes described.

A possible control or regulation of the tempering medium flows through the tempering branches can be suspended for the duration of the method according to the invention. (For the tests presented in the description of the figures, the volume flow control was kept active to record the temperature curves in order to have a constant volume flow.)

The at least one branch temperature profile can be used in the form of a time profile of at least one temperature difference between an inlet temperature and an outlet temperature of the at least one temperature control branch. This means that for the temperature control branch or branches, profiles of the outlet temperatures and the inlet temperature are measured and their difference is used as the branch temperature profile for the respective temperature control branch.

Alternatively, it can be assumed in many cases that the inlet temperature from a common inlet is the same for all temperature control branches (and essentially constant) and that an outlet temperature curve is simply used as the branch temperature curve of the respective temperature control branch.

The at least one temperature control branch can also be classified, for example, in at least three (or more) categories, which include at least three categories, at least one category with a major influence on the heat balance of the section of the mold and at least one category with a medium influence on the heat balance of the section of the mold and at least one category of low impact on the thermal management of the portion of the mold. The more and thus more finely granulated categories are used, the more individually the setpoints for the control or regulation of the tempering branches can be specified.

At least one of the method steps of the method according to the invention (in both variants) can be carried out automatically by a computing unit.

[0097] In this way, the problem on which the invention is based for operators of the shaping machine can not only be solved but also completely eliminated because, for example, the temperature control device provides the desired values for the temperature control all by itself.

The above-mentioned techniques for analyzing the oscillation behavior and/or the rise or fall behavior can be used, using known data evaluation methods, for example for determining Fourier transformations, maximum values, time offsets (time delays) up to a rise or fall or slopes of an increase or decrease.

The temperature control branches can also be referred to as temperature control circuits or as circuits for short, particularly when they are connected in parallel. The production cycles can also be referred to as cycles for short. The duration of a production cycle can be referred to as the cycle time, and the frequency corresponding to this cycle time can be referred to as the cycle frequency.

The analysis according to the invention of the oscillation behavior and/or the rise or fall behavior (and optionally the corresponding categorization) can also be used to monitor the system. For example, if the oscillation behavior and/or the rise or fall behavior changes rapidly, malfunctioning circuits (e.g. clogging), or faulty forming tools or hot runner systems can be concluded. On this basis, for example, warning messages can be issued and/or production can be stopped and/or a heater can be switched off.

[00101] Further details and advantages of the invention result from the figures and the associated description of the figures. show:

1 shows a schematic representation of a molding tool,

2 shows a traced photographic representation of a mold (image source: Wikipedia),

3 examples of branch temperature curves for carrying out the method according to the invention,

4 Fourier transformation of the branch temperature curves,

5 shows a diagram to clarify the classification according to the invention of the temperature control branches into categories,

[00107] FIG. 6 shows the representation of the mold from FIG. 2, with the drawing showing which temperature control branches have which influence on the heat balance of the mold,

7 shows a diagram to illustrate the principle of the propagation of thermal waves used by the invention (image source: Plastverarbeiter),

[00109] FIG. 8 shows a schematic representation of the arrangement according to the invention together with a temperature control device according to the invention and

9 shows a schematic representation of a mold with a hot runner system (image source: Plastverarbeiter).

1 shows a schematic representation of a mold 2 (here the nozzle side of an injection mold) on which the method according to the invention was carried out. Temperature control branches (temperature control circuits) K1 to K4 as well as KX and KY lead through the mold 2 . In this embodiment, the temperature control branches K1 to K4 and KX and KY are connected in parallel in terms of flow technology (similar to FIG. 8).

For the sake of simplicity, however, only the temperature control branches K1 to K4 were used for the method according to the invention in order to reduce the amount of data.

It should be mentioned that the temperature control branches K1 to K4 are not shown according to their actual spatial configuration. The mold cavity 13, which is not shown in FIG. 1, lies approximately in the center of the mold 2 (indicated by the central gray circle).

In order to illustrate how the invention works, temperature sensors 11 (here: thermocouples) were installed in the mold 2 itself in order to show the good correlation between the actual thermal situation in the mold 2 and the data collected according to the invention. The temperature sensors 11 are numbered sequentially as H8x, H9x and H10x. These temperature sensors 11 installed in the mold 2 are of course not absolutely necessary when the method according to the invention is actually carried out in practice.

For the sake of completeness, a simplified heat balance on the injection mold is noted:

Qrm - Qu + Qr +Qu =0

Qru Heat flow that the temperature control medium supplies or removes (heating or cooling with the temperature control medium)

Qu heat flow to the environment

Ör heat flow of the molded part

Qu additional heat flow, for example through hot runners [00116] Simplified heat flow molded part:

. m Qr = Ah —

currently

Ah enthalpy difference mp mass of the molded part tz cycle time Heat flow from the temperature control medium (Qrm is negative for cooling): Qrm - -Qr - Qu - Qu The figure shows the magnitude of the branch heat flows. Qrm = Mrtyu ‘Ct AT = Vrm ‘Pr Ctm AT AT = T7u — Tab

Vru volume flow temperature control medium

Prm density of temperature control medium (approximately constant at essentially constant temperature)

Crm Specific heat capacity of the tempering medium (approximately constant at essentially constant temperature)

AT Difference between inlet and outlet temperature of a temperature control branch

The information as to which temperature control branch K1 to K4 is arranged geometrically in an actual mold 2, in particular how close the individual temperature control branches K1 to K4 pass the mold cavity 13, is often not available in practice. In fact, for a person who is responsible for setting up the forming process, the situation at the forming tool 2 is simply as shown in the photo in Fig. 2.

As shown in the photo, hoses for the supply and removal of tempering medium (water in this embodiment) can be connected, but it is not clear how these tempering branches K1 to K4 lead through the mold 2.

The method according to the invention can be used at this point. In the exemplary embodiment presented here, the production of the molded parts is started first. Since this exemplary embodiment is an injection molding process, production takes place in production cycles, with the mold 2 being closed and subjected to a closing force and then a molding compound 12 (here: plastic) being injected into the mold cavity 13 .

The production cycles within the scope of the method according to the invention can be test cycles or start-up cycles in order to check and/or adapt the correct setting of the shaping machine or to create defined thermal conditions. In many cases, such test cycles have to be carried out anyway when setting up the forming tool 2 .

Before the start of the production cycles, the temperature control medium is started to be conveyed through the temperature control branches K1 to K4. Branch temperature curves RLTO1 to RLTO4 of the temperature control branches K1 to K4 are measured by means of temperature sensors 6 and in the exemplary embodiment presented here also with the temperature sensors 11 arranged in the mold 2 . Analogously, 11 temperature curves H8x and H9x are measured with the temperature sensors. These are shown in FIG.

The individual curves in FIG. 3 are plotted over the time axis. In the present exemplary embodiment, the branch temperature curves RLTO1 to RLTO04 are the direct measured values from temperature sensors 6, which were measured in the course of the temperature control branches K1 to K4, since the temperature control branches K1 to K4 are fed from the same central inlet, so it can be assumed that the inlet temperatures are the same for the temperature control branches K1 to K4. The volume flows of the temperature control branches K1 to K4 were regulated to the same value for the test. The only factor that can be changed over time is the outlet temperature in the respective circuit.

Pre-processing of the measured signals, e.g. by filtering, is of course possible.

The obvious assignment applies: branch temperature profile RLTO1 to temperature control branch K1, branch temperature profile RLTO2 to temperature control branch K2, branch temperature profile RLTO03 to temperature control branch K3 and branch temperature profile RLTO04 to temperature control branch K4.

The vertical dashed lines in the individual diagrams of Fig. 3 indicate movements of the plasticizing screw (screw position) of the injection molding machine used, i.e. an injection process. Each pair of vertical lines therefore approximately indicates a new forming cycle, and the duration between adjacent pairs approximately corresponds to the cycle time.

[00128] It can be seen that the measured values differ in speed and intensity by the

Heat introduced into the mold 2 react at the start of production.

Analysis of the rise behavior: In detail it can be seen that the branch temperature curve RLTO1 reacts fastest to the heat input, the branch temperature curve RLT0O3 reacts next and the branch temperature curves RLT0O2 and RLTO04 react the slowest (and overall relatively weakly).

The time of the first increase (here second cycle at RLTO1 and third cycle at RLTO03) in the form of a time interval since the start of production (injection processes) can be determined automatically by known data evaluation methods.

The greatest change in the branch temperature in terms of absolute value occurs in temperature control branch K1, followed by K3. Smaller increases occur in the temperature control branches K2 and K4 (the branch temperature curves RLTO01 to RLTO4 from FIG. 3 are scaled the same).

In addition, it can be seen that branch temperature profile RLTO1 and, to a somewhat lesser extent, branch temperature profile RLTO3 correlate with the oscillations that occur in the measured values H8x and H9x of the temperature sensors 11 arranged in the mold 2 . This shows that the influence that an individual temperature control branch K1 to K4 has on the thermal balance of the mold 2 is clearly reflected in these measured values, which is not necessarily to be expected due to the complex thermal situation in the mold 2.

Analysis of the oscillation behavior: This correlation of the oscillations in the branch temperature curves RLTO1 to RLTO04 can be analyzed relatively easily using a Fourier transformation.

The Fourier transformations of the measurement curves from FIG. 3 are shown in FIG. The X-axis was scaled in units of multiples of the cycle frequency (i.e. the reciprocal values of the multiples of the cycle times).

It can be clearly seen that in FIG. 4 the Fourier transforms of the branch temperature curves RLTO1 and RLT0O3 result in maxima when the cycle frequency is multiplied, which also match well with the corresponding maxima in the measured values H8x and H9x of the temperature sensors 11 in the tool.

The amplitudes of the oscillations in the branch temperature curves RLTO1 to RLTO4 can also be determined using the measured values from FIG. 3 and compared with one another. Again, the result is that the amplitudes in the area of the simple cycle frequency are strongest for branch temperature curve RLTO1, second strongest for branch temperature curve RLT03 and weakest for branch temperature curves RLTO2 and RLT04.

The maxima of the branch temperature curves RLTO1 to RLTO04 and the maxima of the Fourier transform of the branch temperature curves RLTO1 to RLTO4 can also be determined automatically using data evaluation methods that are known per se.

It should be mentioned that the branch temperature curves RLTO1 to RLTO04 each have maxima of different heights at slightly more than half of the cycle time. It is likely that there are fluctuations in the temperature of the temperature control medium that is supplied. In principle, these could be eliminated by measuring the flow temperature and subtracting the branch temperature curves RLTO1 to RLT04.

Fig. 5 illustrates an embodiment of the logic when classifying the temperature control branches K1 to K4 in categories (which were numbered 1, 2 and 3) with regard to the influence on the molded part (the quality of the molded part).

After the above-described analysis of the rise behavior (time delay, rise, heat flow), the amplitude of the oscillation behavior and the frequency of the oscillation behavior, the temperature control circuits K1 to K4 can be classified into three categories (evaluation of the position of the temperature control channel in relation to the cavity/influence on the molded part). .

In the present exemplary embodiment, for example, the temperature control branch K1 belonging to the branch temperature profile RLTO1 would be according to all three criteria (rise behavior, amplification

tude, frequency) in category 1 (fastest rise, largest amplitude, highest maximum of the Fourier transformation with the simple cycle time).

This is followed by the temperature control branch K3 associated with the branch temperature curve RLT0O3 in category 2 and the temperature control branches K2 and K4 associated with the branch temperature curves RLTO2 and RLTO4 in category 3.

Accordingly, the temperature control branches K1 to K4 are divided into three categories:

Category 1: Temperature control branch K1 Category 2: Temperature control branch K3 Category 3: Temperature control branches K2 and K4

Instead of a relative categorization (greatest influence: category 1, least influence: category 3) of the temperature control branches K1 to K4, absolute criteria for classifying the temperature control branches K1 to K4 in the categories could also be used.

An example would be to classify those temperature control branches K1 to K4 whose times of the first increase are less than X1 cycles after the start of production in category 1, - those temperature control branches K1 to K4 whose times of the first increase are more than X1, but are less than X2 cycles after the start of production, to be classified in Category 2, and - those temperature control branches K1 to K4, whose times of the first increase are more than X2 cycles after the start of production, to be classified in Category 3, with X1 < X2 < X3 is. This could also be done analogously for the amplitude or the correlation with the cycle frequency.

Examples of the limit values would be X1=3 and X2=6.

Critical temperature control branches K1 to K4 (ie important for the quality of the molded part to be produced) are those which have to dissipate large heat flows and/or which are located close to the cavity surface. The assessment is made with regard to

- the size of the heat flow and/or the amplitude of the heat flow in the temperature control branch K1 to K4 and/or the size of the change in the amplitude due to the start/end of molded part production/hot runner switching, ”

- the proximity to the cavity surface, e.g. due to the rate of change of the heat flow in a temperature control branch K1 to K4 (how quickly does the heat flow increase in which branch?) and the time offset to the first injection (the shorter the time, the closer) and

- Proximity to the cavity surface, e.g. by recognizing the simple cycle frequency (the closer a temperature control branch K1 to K4 is to the mold cavity 13, the earlier the cycle frequency in the temperature control branch K1 to K4 can be identified; the closer a temperature control branch K1 to K4 is to the mold cavity 13 , the better the cycle frequency can be seen; with the latter: less interference, reflections, ...)

As mentioned, the categories can be defined on the one hand on the basis of predefined limit values for the distinguishing variables mentioned, as a result of which the invention can also be used with a single temperature control branch.

[00149] Embodiments can be particularly preferred in which a “most critical” temperature control branch is used as a reference for category 1 and the other temperature control branches are defined via relative limits (for example in the form of percentage values).

According to the categorization of the temperature control branches K1 to K4 according to the invention, the target values, in this exemplary embodiment target temperature differences, can also be specified, namely a low target temperature difference for the temperature control branch K1, an average target temperature difference for the temperature control branch K3 and a higher target Temperature difference for the temperature control branches K2 and K4.

As desired, this results in a higher volume flow through the tempering branch

K1, an average volume flow through the temperature control branch K3 and a lower volume flow through the temperature control branches K2 and K4 (relative to a maximum possible volume flow through the respective temperature control branch). The volume flow resulting from a controlled temperature difference is also dependent on the heat flow introduced in the respective temperature control branch.

For example, the following target temperature differences could be specified for the categories:

Category 1 1°C 1°C Category 2 2°C or 3°C Category 3 3°C 5°C

[00153] It would of course also be conceivable for the operator to specify the target values based on the classification of the temperature control branches K1 to K4 in the categories.

Alternatively, target volume flows for the individual temperature control branches K1 to K4 could also be determined directly.

Even if setpoints for the control or regulation of the temperature control medium flows through the temperature control branches K1 to K4 are not directly specified, important information for the operator results from the method according to the invention, simply because the temperature control branches K1 to K4, which are critical for the quality of the molded parts to be produced become known, which is illustrated in the photo from FIG. 6 (the detection of temperature control branches K1 to K4 with greater influence on a section 3 of the mold 2 with a hot runner system 14 is described in connection with FIG. 9). Thus, Figure 6 could be considered as a simple representation of the result of the invention.

If an error occurs in a critical or cavity-near circle (category 1), it is clear to the operator through the findings from the application of the invention that this error can have a direct influence on the quality of his molded part.

[00157] Possible actions can be error messages triggered by the control unit or a production stop of the machine.

A non-critical circuit (category 3) can be treated differently in the event of an error. For example, the control unit can only trigger an information message, but not stop production immediately.

If, for example, there are only manual valves for setting throttles for the individual temperature control branches K1 to K4, operators can set these manual valves sensibly on the basis of the categorization mentioned (e.g. fully open for temperature control branch K1, medium opening degree for temperature control branch K3 and low degree of opening for the Temperature control branches K2 and K4).

In any case, better temperature control of the mold 2 with regard to the quality of the molded parts and intelligent distribution of the limited temperature control medium can be achieved.

FIG. 7 illustrates the basic physical relationship by means of which, according to the invention, the influence of the temperature control branches K1 to K4 on the heat balance of the mold 2 and thus the quality of the molded parts to be produced can be determined.

If temperature sensors 11 are arranged in a mold 2 at certain distances (see positions P1 to P3 in FIG. 8) from a mold cavity or mold cavity 13, the temperature profiles T1 to T3 shown on the right in the diagram in FIG. 8 result.

The position P3 is on the cavity wall, position P2 is at a certain distance therefrom in the mold 2 and position P1 at an even greater distance. Due to the molding material 12, which is introduced into the mold nest/the mold cavity 13, a steep temperature profile T3 with a characteristic shape (periodic oscillation) results at position P3. The comparison with the temperature profiles T2 and T1 shows that the steep and

characteristic shape quickly weakens in its amplitude and the characteristic shape changes significantly due to the more sluggish heat propagation compared to the shaping cycle. A central aspect of the invention is the knowledge that systematic analysis can nevertheless be used to identify in a reproducible manner which temperature control branches K1 to K4 play which role in the heat balance of the mold 2 . The closer a circle is to the cavity surface, the more pronounced are the characterization features considered.

This means that a temperature control branch at a distance P1 would have significantly less influence on the molded part than a temperature control branch at a distance P2 due to the greater distance. As a result, the volume flow could be reduced there, in particular the temperature difference could be increased.

An advantage of the invention is that no temperature sensors have to be installed in the tool in order to detect whether a temperature control branch is placed near the cavity, but the temperature curve in the temperature control medium can be used for the categorization. This means that any tools can be categorized, regardless of the sensors installed in them.

In summary, the following physical effects in particular play a significant role in the heat balance of the mold 2: - Cyclic oscillation of the heat flow (or the surface temperature) through the molding process (injection molding process) on the cavity surface - Propagation of the thermal wave in the tool steel - The amplitude of thermal waves increases by increasing the introduced heat flow per area or reducing the frequency (both are approximately constant in injection molding, for example) - Decaying amplitude of the heat flow with increasing distance, damping by tool steel - As a result, high heat flow on temperature control branches K1 to K4 at points where high heat flow is introduced - The heat flow requires time to spread in the mold 2 - The heat flow can therefore be measured earlier on those temperature control branches K1 to K4, which are close to the mold cavities 13 - The cycle frequency (or cycle time) can therefore be identified from the heat flow in the Temperature control branch K1 to K4

In addition, this frequency or the increase in the heat flow can be seen earlier if the temperature control branch K1 to K4 is located close to the mold cavity 13 .

With a constant volume flow, the temperature difference in the temperature control branch can be used instead of the heat flow. If the flow temperature is also constant, the outlet temperature of the tempering branch can be used.

The invention can also be used in heating duct systems (see Figure 9). Hot runner systems usually have their own temperature/power control. The controlled variable is normally the temperature of a hot runner zone. However, the hot runner can only be heated (output level for heating output). Cooling by the medium in the adjoining temperature control branches is required for regulation and heat dissipation. Without adequate cooling, the zone can overheat. Since the hot runner system has its own control, a stable temperature is set if there is sufficient cooling.

It would be conceivable to use the information about a sufficiently available temperature control medium volume flow in the temperature control branches determined by the invention with relevance for the hot runner in order to enable/initiate the switching on or lowering/switching off of the hot runner zone.

A simple example: If the temperature control branch is relevant for the hot runner zone and not enough water flows (because, for example, the temperature control branch was not switched on or there is a blockage in the temperature control branch), switching on the hot runner zone (or the entire hot runner system) can be prevented be or a shutdown or at least one

Lowering to a non-critical temperature can be initiated. Of course, this can be done on the basis of the relationship found between the hot runner and temperature control branches.

If the hot runner with its manipulated variable is at the lower limit and the target temperature can still not be reached (hot runner threatens to overheat), the volume flow in the relevant temperature control branch can be increased in order to dissipate a higher heat flow and enable control. If the hot runner with the output level is at the upper limit (i.e. does not reach the desired temperature), the volume flow can be reduced so that less heat is dissipated and heating is possible.

8 shows an arrangement according to the invention of a molding machine 10 (here by way of example an injection molding machine) with a temperature control device 1 according to the invention.

The molding tool 2 is clamped in the molding machine 10 . Temperature control branches K1 to K4, which in this exemplary embodiment are fluidically connected in parallel, lead through the mold 2 .

It should be mentioned that only those line sections are to be understood as temperature control branches K1 to K4 in the actual sense that are present within the mold 2 and thus actively participate in the heat balance of the mold 2 (the arrangement of the reference numbers is due to the clarity of the illustration ).

Other hose and line sections (inlet/flow on the one hand and outlet/return on the other) leading to and from the temperature control device 1 are of course still present in almost all cases, but they practically do not impair the method according to the invention.

The temperature control device 1 according to the invention initially includes a conveyor device 7 for generating the volume flow that is conveyed through the temperature control branches K1 to K4.

A temperature sensor 6 is then provided in this exemplary embodiment in order to measure the temperature profile of the medium supplied. Particularly when the temperature control branches K1 to K4, as here, are fed from a common feed and the feed temperature is fairly constant, this temperature sensor 6 does not necessarily have to be present in the feed.

The conveyor device 7 can also be located at a spatial distance from the temperature control device.

This is followed by actuators 4 (here electrically or electronically controllable throttles with an adjustable degree of throttle) for influencing the volume flows through the individual temperature control branches K1 to K4. In terms of flow, these could also be installed downstream of the mold 2 in the temperature control branches K1 to K4.

[00181] After the tempering media streams have passed through the mold 2, they are fed back to the tempering device 1 again. At this point, volume flow sensors 17 and further temperature sensors 6 are provided individually for the temperature control medium flows, by means of which the volume flows through the temperature control branches K1 to K4 and the branch temperature curves RLTO1 to RTLO4 can be measured. For use in the method according to the invention, it can be provided that the measured values recorded by the temperature sensor 6 arranged in the flow are subtracted from the measured values of the other temperature sensors 6 and the branch temperature curves RLTO1 to RTLO4 are used in this form as a temperature difference in order to eliminate possible temperature fluctuations in the flow . As mentioned, this is not necessary in all cases.

In principle, the measured values of the volume flow sensors 17 can also be taken into account in the categorization according to the invention of the temperature control branches K1 to K4.

The processing unit 5 is connected in terms of signals to the temperature sensors 6 for measuring the branch temperature profiles RLTO1 to RTLO4, preferably also to the central machine controller 9, for example to provide information about the cycle time and the beginning of the

Production and / or the supply of the molding compound 12 to obtain at least a portion 3 of the mold 2.

The computing unit 5 is designed to carry out the above-described method according to the invention. In particular, it is provided in this exemplary embodiment that the arithmetic unit 5 automatically predefines target temperature differences individually for the individual temperature control branches K1 to K4 on the basis of the method according to the invention.

Furthermore, the temperature control device 1 in this exemplary embodiment has a control or regulating device 8, which is also connected in terms of signals to the temperature sensors 6, the volume flow sensors 17 and the actuators 4 in order to carry out a known control or regulation according to the temperature difference of the carry out individual temperature control branches K1 to K4.

In addition, it is provided in this exemplary embodiment that the control or regulating device 8 carries out a subordinate control or regulation of the volume flows through the temperature control branches K1 to K4 on the basis of the temperature difference regulation, for which the actuators 4 are activated accordingly.

The control or regulating device 8 can be connected to the processing unit 5 (and/or the central machine control) in terms of signals, for example in order to obtain the setpoint values specified according to the invention or to receive a signal that the actuators 4 are required to carry out the method according to the invention are equated, in particular fully opened, and/or the open-loop or closed-loop control is to be suspended for the duration of the method according to the invention.

Signaling connections are not shown in FIG. 8 in order to preserve the clarity of the illustration.

The computing unit 5 can be designed integrally with the central machine control 9 of the shaping machine 10 and/or the control or regulating device 8 of the temperature control device 1 .

Fig. 9 schematically shows the structure of a mold 2 (injection mold) with a hot runner system 14. During normal operation, a plasticized plastic is conveyed as a molding compound 12 during the injection process through the hot runner system through the hot runner nozzles 15 and finally into the mold cavity 13.

The method according to the invention makes it possible to identify those temperature control branches K1 to K4 (only one of the temperature control branches is provided with a reference number in FIG. 9) which have a stronger heat coupling to the hot runner system 14 .

For this purpose, some of the hot runner nozzles 15 are closed and thus only that section 3 of the mold 2 is filled with molding compound 12 which is in the vicinity of the open hot runner nozzles 15 . Analysis of the increase behavior of the branch temperature curves will show that those temperature control branches K1 to K4, which are to the right of the mold cavity 13 in Fig. 10, have a greater influence on the heat balance of section 3 (i.e. the area around the hot runner system 14) of the mold 2 than those which are to the left of the mold cavity 13 in FIG. It can thus be recognized with the invention which of the plurality of temperature control branches K1 to K4 are close to the hot runner system 14 and which are not.

This could even be used to detect series and/or parallel circuits in hot runner systems 14 .

[00194] A step-by-step switching on of heating zones of the hot runner system 14 can also enable an exact allocation in this regard.

As already mentioned, only a single mold cavity 13 or a group of mold cavities 13 could be examined as section 3 of a mold 2 with a plurality of mold cavities 13 .

In a similar way can be recognized with the method according to the invention, wel

che temperature control branches K1 to K4 are arranged in the vicinity of an injection unit and/or an injection nozzle of an injection molding machine.

Finally, the method according to the invention could also be used in the construction of a virtual thermal tool model by analyzing an oscillation behavior and/or an increase or decrease behavior in simulations. The following objects would then be present as virtual objects: the temperature control device 1 and/or the molding tool 2 and/or the actuators 4 and/or the temperature sensors 6 and/or the conveyor device 7 and/or the molding machine 10 and/or the temperature sensors 11 and /or the molding compound 12 and/or the mold cavity/mold cavity 13 and/or the hot runner system 14 and/or the hot runner nozzle 15 and/or the ejector 16 and/or the temperature control branches K1-K4.

The measured parameters of the temperature control branches of the real mold can also be compared with these calculated parameters of the temperature control branches of a mold model from an injection molding simulation. The characteristic thermal behavior of the individual temperature control branches can be compared with the results of the simulation in order to create an association between the circuits of the temperature control device (real structure on the machine) and the circuits of the simulation model. Based on this assignment, setpoint values (e.g. volume flow or temperature difference) for the corresponding temperature control branches can be set correctly in the simulation or in a data set, or the correct tubing of the circuits can be checked.

REFERENCE LIST:

temperature control device 1

Form tool 2

at least one section 3 (of the mold) actuators 4

Computing unit 5

Temperature sensors 6 Conveyor 7

Control or regulation unit 8

Central machine control 9 molding machine 10 temperature sensor 11 (in the mold) molding compound 12

Mold cavity/mold nest 13 Hot runner system 14

Hot runner nozzle 15

Ejector 16

Volumetric flow sensors 17

Temperature control branches K1-K4 Branch temperature profiles RLTO1-RLTO4 positions P1-P3

Temperature curves T1-T3

Claims (20)

patent claims 1. A method for classifying at least one temperature control branch (K1-K4) of a mold (2) according to an influence on a heat balance of at least one section of the mold (2), the following method steps being carried out: - Production of molded parts in production cycles by means of at least one section (3) of the mold (2) with input of heat into the mold (2) and/or cyclical activation of a heating device with input of heat into the mold (2), - conveying temperature control medium through the at least one temperature control branch (K1-K4) of the mold (2) to dissipate at least part of the heat introduced, - Measuring at least one branch temperature profile over time (RLTO01-RLT04) of the temperature control medium in at least one temperature control branch (K1-K4) over several production cycles, - Analysis of an oscillation behavior of the at least one branch temperature curve (RLTO1-RLTO04) and/or a variable derived from the at least one branch temperature curve, in particular at least one branch heat flow, over a number of production cycles, and - Classifying the at least one temperature control branch (K1-K4) in one of at least two categories according to greater and/or lesser influence on the heat balance of the at least one section (3) of the mold (2) based on the oscillation behavior. 2. The method according to claim 1, characterized in that for dissipating at least part of the heat introduced, temperature control medium is conveyed through temperature control branches (K1-K4) of the mold (2), branch temperature curves (RLTO1-RLT04) over time of the temperature control medium in the temperature control branches (K1- K4) are measured over several production cycles, which branch temperature curves (K1-K4) are subject to different fluctuations due to different levels of and/or faster heat transfer of the heat introduced into the mold (2) to the respective temperature control branch (K1-K4), differences occurring in the oscillation behavior between the branch temperature curves (RLTO1-RLT04) and/or the size of the temperature control branches (K1-K4) derived from the at least one branch temperature curve and the temperature control branches (K1-K4) based on the differences in the oscillation behavior according to greater and/or less influence on the Heat balance of the at least one section (3) of the mold (2) can be classified in one of the at least two categories. 3. The method according to claim 1 or 2, characterized in that as part of the analysis of the oscillation behavior, an amplitude, a frequency and/or a period of the at least one branch temperature curve (RLTO1-RLT04) and/or the variable derived therefrom is determined and, if necessary, Determining the differences in the oscillation behavior is used. 4. The method, in particular according to one of claims 1 to 3, for classifying at least one temperature control branch of a mold (2) according to an influence on a heat balance of at least one section (3) of the mold (2), the following method steps being carried out: - Supplying a molding compound (12) at least to the section (3) of the mold (2) with the input of heat into the mold (2) and/or activating a heating device with the input of heat into the mold (2), - conveying temperature control medium through the at least one temperature control branch (K1-K4) of the mold (2) to dissipate at least part of the heat introduced, - Measuring at least one branch temperature profile over time (RLTO1- RLTO4) of the tempering medium in at least one tempering branch (K1-K4), - Analysis of a rise or fall behavior of the at least one branch temperature profile (RLTO1-RLTO04) and/or a variable derived from the at least one branch temperature profile, in particular at least one branch heat flow, and - Classification of at least one temperature control branch (K1-K4) in at least two categories 10 11. 12. Austrian AT 525 419 B1 2023-05-15 according to greater and/or lesser influence on the heat balance of the at least one section (3) of the mold (2) on the basis of the increase or decrease behavior. Method according to Claim 4, characterized in that, in order to dissipate at least part of the heat introduced, the temperature control medium is conveyed through temperature control branches (K1-K4) of the mold (2), branch temperature profiles (RLTO1-RLT04) over time of the temperature control medium in the temperature control branches (K1-K4) be measured, which branch temperature curves (K1-K4) are subject to different fluctuations due to different strength and/or speed of heat transfer of the heat introduced into the mold (2) to the respective temperature control branch (K1-K4), differences occurring in the rise or fall behavior between the branch temperature curves ( RLTO1-RLTO04) and/or the size of the temperature control branches (K1-K4) derived from the at least one branch temperature curve and the temperature control branches (K1-K4) based on the differences in the rise or fall behavior according to greater and/or less influence on the Heat balance of the at least one section (3) of the mold (2) can be classified in one of the at least two categories. Method according to Claim 4 or 5, characterized in that as part of the analysis of the rise behavior, a time of the first rise above a threshold value in the at least one branch temperature profile (RLTO1-RLT04) is determined and, if necessary, used to determine the differences in the rise behavior. Method according to one of the preceding claims, characterized in that at least one setpoint for controlling or regulating the flow of temperature control media conveyed through the at least one temperature control branch (K1-K4) is defined on the basis of the category of the at least one temperature control branch (K1-K4). Method according to Claim 7, characterized in that at least one setpoint temperature difference between an inlet temperature and an outlet temperature of the at least one temperature control branch (K1-K4) is used as at least one setpoint value, with the setpoint temperature differences for temperature control branches (K1-K4) preferably having greater influence on the heat balance of the at least one section (3) of the mold (2) in terms of magnitude lower than the setpoint temperature differences for temperature control branches (K1-K4) with less influence on the heat balance of the at least one section (3) of the mold (2). become. Method according to Claim 7 or 8, characterized in that at least one target volume flow is used as at least one target value, with the target volume flows for temperature control branches (K1-K4) having a greater influence on the heat balance of the at least one section (3) of the Mold (2) relative to a maximum achievable volume flow are selected larger than in temperature control branches (K1-K4) with less influence on the heat balance of at least one section (3) of the mold (2). Method according to one of the preceding claims, characterized in that actuators (4) for the controlled or regulated influencing of the temperature control medium flow conveyed through the at least one temperature control branch (K1-K4) are equalized at the beginning of the method, in particular are fully opened. Method according to one of the preceding claims, characterized in that several temperature control branches are used and the actuators (4) for the controlled or regulated influencing of the temperature control medium flows conveyed through the temperature control branches (K1-K4) are set at the beginning of the method in such a way that the temperature control medium flows through the Tempering branches (K1-K4) are equal. Method according to one of the preceding claims, characterized in that the at least one branch temperature profile (RLTO1-RLTO04) is used in the form of a time profile of at least one temperature difference between an inlet temperature and an outlet temperature of the at least one temperature control branch (K1-K4). 13. 14 15 16 17 18 Austrian AT 525 419 B1 2023-05-15 Method according to one of the preceding claims, characterized in that the at least one temperature control branch (K1-K4) is assigned to one of at least three categories, which include at least three categories and at least one category having a major influence on the heat balance of the section (3) of the mold (2nd ), at least one category of moderate influence on the heat balance of section (3) of the mold (2) and at least one category of low influence on the heat balance of section (3) of the mold (2). Method according to one of the preceding claims, characterized in that at least one of the method steps of the method according to one of the preceding claims is carried out automatically by a computing unit (5). Tempering device for tempering a mold (3), in particular set up tet for carrying out a method according to any one of the preceding claims, with - a conveying device (7) for conveying temperature control medium through at least one temperature control branch (K1-K4) of the mold (3), - A computing unit (5) and - at least one temperature sensor (6) connected to the processing unit (5) for signaling purposes, which is set up to measure at least one branch temperature profile over time (RLTO1-RLTO04) of the temperature control medium in at least one temperature control branch (K1-K4), characterized in that the computing unit (5) is set up to - carry out an analysis of a rise or fall behavior and/or an oscillation behavior of the at least one branch temperature profile (RLTO1-RLT04) and/or a variable derived from the at least one branch temperature profile, in particular at least one branch heat flow, preferably over several production cycles, and - classify the at least one temperature control branch based on the rise or fall behavior and/or the oscillation behavior in one of at least two categories according to greater and/or lesser influence on the heat balance of at least one section (3) of the mold (2). Temperature control device according to Claim 15, characterized in that a plurality of temperature control branches (K1-K4) and a plurality of temperature sensors (6) are provided and the computing unit (5) is designed to detect differences between the branch temperature profiles ( RLTO1RLT04) of the temperature control branches (K1-K4) and determine the temperature control branches on the basis of the differences found in the increase or decrease behavior and/or in the oscillation behavior after greater and/or less influence on the heat balance of at least one section (3) of the mold (2) in classified into one of the at least two categories. Shaping machine with a temperature control device (1) according to claim 15 or 16, wherein the shaping machine (10) is preferably designed to produce shaped parts in shaping cycles. Computer program product for classifying at least one temperature control branch (K1-K4) a molding tool (2) after an influence on a heat balance at least one Section (3) of the mold (2), in particular for carrying out a method according to any one of claims 1 to 14, comprising instructions which an executing computer cause - to receive measured values in the form of at least one branch temperature profile over time (RLTO1-RLT04) of a temperature control medium conveyed through at least one temperature control branch (K1-K4) of the mold (2), the measured values preferably being available over several production cycles, - An analysis of a rise or fall behavior and / or an oscillation behavior of the at least one branch temperature profile (RLTO1- RLT04) and / or from the 24/31 carry out at least one variable derived from the branch temperature curve, in particular at least one branch heat flow, preferably over a number of production cycles, and - the at least one temperature control branch (K1-K4) based on the rise or fall behavior and/or the oscillation behavior in one of at least two categories according to greater and/or lesser influence on the heat balance of the at least one section (3) of the mold (2) classify 19. Computer program product according to claim 18, characterized in that the instructions cause the executing computer to - to receive the measured values in the form of branch temperature curves (RLTO1-RLTO04) of the temperature control medium conveyed through the temperature control branches (K1-K4) of the mold (2), which branch temperature curves (RLT01-RLT04) due to different strength and/or speed of heat transfer from into the mold (2) input heat on the respective temperature control branch (K1-K4) are subject to different fluctuations, - Determine differences between the branch temperature profiles (RLTO0O1-RLT04) of the tempering branches (K1-K4) in the oscillation behavior and/or in the rise or fall behavior and - the temperature control branches (K1-K4) on the basis of the differences found in the increase or decrease behavior and/or in the oscillation behavior according to greater and/or less influence on the heat balance of the at least one section (3) of the mold (2) in one of the at least classified into two categories. 20. Computer-readable storage medium on which a computer program product according to claim 18 or 19 is stored. 6 sheets of drawings